> Hi,> > On Thu, Oct 13, 2011 at 10:31 PM, Alan Stern <stern@rowland.harvard.edu>> >> Maybe we should understand the correct model of the ordering constraints> >> for the multiple device dependancies first, could you give a description or> >> some examples about it?> >> > The requirement is that devices must be capable of resuming in the> > order given by dpm_list, and they must be capable of suspending in> > the reverse order.> >> > Therefore if device A can't work unless device B is functional, then B> > must come before A in dpm_list.> > If all devices can support async suspend and resume correctly, looks like> the device order given by dpm_list is not needed any longer, doesn't it?

It _is_ needed, because the user can disable async suspend/resume via /sys/power/pm_async.